Incandescent electric lamp.



I PATENTED AUG. 23', 1904. 1). J. O'BRIEN. INCANDESOENT ELECTRIC LAMP.

APPLIOATION FILED MAY 25. 1903.

N0 MODEL.

IlNiTEn STATES I P T T OFFICE.

Patented August 23, 1904.

DENNIS JOSEPH OBRIEN, OF SAN FRANCISCO, CALIFORNIA, ASSIGNOR, BY DIRECTAND MESNE ASSIGNMENTS, TO THE OBRIEN REFLECTOR AND ELECTRIC TUBE LAMPCOMPANY, OF SAN FRANCISCO, CALIFORNIA,- A CORPORATION OF CALIFORNIA.

INCANDESCENT ELECTRIC LAMP.

SPECIFICATION forming part of Letters Patent No. 768,479, dated August23, 1904.

. Application filed May 25, 1903- To all whom it may concern: Be itknown thatI, DENNIS JOSEPH OBRIEN,

a citizen of the United States of America, and

a resident of the city and county of San Francisco, in the State ofCalifornia, have invented a new and useful Incandescent Electric Lamp,

manufacture of this class of lamps.

' A second object correlative of the above is so .to anchor the filamentas to keep it uniformly straight and under every thermal or antithermalcondition, thereby preventing or 5 at least minimizing its vibrationfrom any cause and further precluding its coming into contact with orgetting dangerously near the walls of the surrounding tube, owing toflexure, or by bowing or sagging, this notwith- 3 standing the filamentsgreater than ordinary length and corresponding tenuity. Another objectis to reduce to the smallest practicable dimensions the metalliccontacts needed to place the lamp electrically incircuit and to solocate the same that facing the lamp one will see nothing but the glasstube and filament therein nor anything else on any side except'a tinymetal piece at either end. and when the lamp is lighted the viewer will4 behold an unbroken line of light and a luminous sheath thereforshining brightly from tip to tip with no'furnishingsor appendages tobreak its continuity and impair its brilliancy.

A further object is to provide a ready and convenient means ofattachment for the lamp,

whereby it can be suspended, framed, or

Serial No. 158,726. (No model.)

bracketed and heldin any desirable position in perfect safety both asregards itself and its mounting.

A still further general object is to produce a superior lamp involving amode of manufacture that is simplified and cheapened and easilypracticed with better, surer, and more enduring results than heretofore.

Proceeding now, to a detailed description of the invention, referencewill be-made tothe accompanying drawings, in which every parthereinafter specified is illustrated and given its own designatoryletter wherever it appears in the several figures. p

Figure 1 is a. side elevation showing. the lamp partly broken andsectioned at one end in order to expose the mannerof fixing the anchorsfor the filament in the under or rear wall of the glass tube and ofappending thereto the metal contact-pieces. Fig. 2 is a similar view ofthe complete lamp with its contacts and attachments, the latterpartially broken and sectioned. Fig. 3 is a cross-section on the line AB of the preceding figure looking to the right. Fig. 4 is a partial plangiving a top view of a spring-anchor seen in elevation in Figs. 1 and 2.Fig.5 is a broken side elevation of a lamp embodying the same principleas that illustrated in the other views, but involving a variation in themethod of anchoring the filament at one end.

The body of the lamp and the filament therein are respectivelydesignated by the reference-letters a and b. The former consists of atransparent glass receptacle in the shape of a tube, usually straightand sealed at both ends. The latter is an ordinary carbon thread, butruns in a single line along the axis of its tubular envelop. Anchors 0and d are provided at or near each end of the tubular'lampbody a inorder to sustain the filament bwithin it in the correct centralposition, as shown in the various figures of the drawings. These anchorsare conveniently made of platinum wire. In the preferred form-ofconstruction both anchors c d are fixed in the under side or rear wallof the tube a, thence rise to about the middle of the tube transverselythereof, and after being bent away from the filament have their innerends turned toward it, so as to be in line with and be jointed to itsends at 0 all as indicated in Figs. 1 and 2. The bend of the anchor 0,it will be seen, is a plain angular bend 9, while that of the anchor (Zconstitutes a coil or loop it, which is flattened, as shown in Fig. 4:,and forms a spring that tends to uncoil away from the filament and pullit oppositely to the anchor c. The latter-named anchor also has more orless of a spring action, and therefore the two anchors c and cl can beconsidered as spring-anchors oppositely located and acting in oppositedirections. To distinguish them structurally, however, the first may becalled an angular spring-anchor and the second a looped spring-anchor.The outer end of each is sealed in the side of the tube, through whichit passes and from which it slightly projects outward, as represented atam the sectioned part of Fig. 1 on the left.

Itis understood that the filament b is mounted in the manner above setforth, while the tube 64 remains open at both ends, and that all thework involved in securely anchoring it and adjusting it with adequateprecision can be performed before the tube need be closed at either end.The manipulation of the several parts is thereby rendered easy ascompared with what it is when both ends of the filament are jointed tostraight platinum wires fastened to the corresponding extremities of thetube,.as was done formerly and as is illustrated for the left end onlyof the tube in Fig. 5. It should be apparent that when the platinumwires extend straight out from the extremities of the filament in themanner last referred to, and consequently must be sealed in by closingthe ends of the tube, the filament is not capable of the same delicateor thorough adjustment, nor can it be expected to give as good andlasting results as are obtainable by following the improved methodherein disclosed. However, it is not necessary to leave both ends of thetube open till the filament is finally adjusted in order thatdemonstrates.

fair results may be obtained, as Fig. 5 clearly In this figure only oneof the two bent anchors is retained, the anchor d. The other, 0, isreplaced by a straight anchor consisting of a platinum wire sealed inone end of the tube a, the left end, as shown. The anchor OZ beingretained, it will be readily perceived that the tension put upon thefilament can be perfectly adjusted after closing the end of the tube inwhich the anchor is sealed. The closing or sealing of the tube at theends is equally well and easily effected in either case whether theanchors c d or jd be employed, and in neither case is it necessary oruseful in exhausting the lamp of air to do so through a specially-madeopening, as in the case of other tube-lampsthat is to say, by usingalateral vacuum-tube or what lamp-makers term a tubulatingtube. Fig. 5plainly shows in addition that it is not indispensable to have twospring-anchors. One will sullice, and the two anchors need not belocatedon the side or on the same side of the tube, the. only essentialrequisite of their combination being that one of them, if not the pair,be transverselydisposed with relation to the filament and shall at thesame time exert an endwise pull thereon, which permits the filament tobe completely adjusted before the tube is entirely closed or sealed asdistinguished from the cases when such adjustment takes place or isattempted while the closing or sealing is being done. As the spring ofthe pair of anchors will relax outward or endward in the inelosing tube,it is evident that the filament will always be kept straight by andbetween them, the lilament actingwhen cold or contracted to keep eachanchor under a greater or lesser tension and when hot or expanded havingits slack taken up by their said spring or springs becoming relaxed.Provision is thus made for an even or equable straightness of thefilament whether it be burning or not or regardless of the presence orabsence of the electric current under any climatic condition, and thereis secured a single-line illuminator that can be more than double thelength of the incandescing loop of the ordinary electric lamp withoutcorresponding increase in cross-sectional area and whose length, infact, is limited only by the voltage. to be carried.

To properly adapt the lamp for connection in an electric circuit, theouter end of each one of the anchors a and (Z or j and (Z is coveredwith a small bell Z, preferably of brass or copper, which bell alsoprotects the sealed opening in the glass tube through which the saidouter end of the anchor passes in each instance. As seen in Fig. 1, theglass is drawn out where the anchor passes through, forming a smalloutwardly-projecting gland which not only furnishes a congruent settingfor the anchor, but also affords a convenient bearing for the bell. Eachbell is soldered to its respective anchor end, as at m, Fig. l, and iscemented to the glass, as at n, in the same figure. Were the bells to belarge and their respective connections with the anchors extended, thenthey would not be soldered directly, as economy would require the use ofintervening wires less costly than platinum copper wires, for example;but such are not required with the small-sized bells shown in thedrawings. Bells of approximately the size shown are used by preferencebecause they are not seen from the face of the lamp when disposed as inFig. 1, so that when the lamp is burning there is not a dark or anobscure spot on it anywhere throughout its length as viewed frontwise,both terminals of the lamp being on the side. This, it will be observed,is of capital importance when several lamps are placed or fittedtogether for instance, end to bells is of the tube a overspring-contacts 0 0,

to which the circuit-wires p p are respectively attached and whichspring-contacts are inclosed in insulating-tubes q q, held to the glasstube of the lamp by clamps r 0. Two contacts, of course, are provided,and they are identical in form and construction, only they areoppositely turned. Each contact, as shown in Figs. 2 and 3, comprises aflat curved spring, (marked 0,) a small cups at theupper end thereof,adapted to receive the bell ha partly-cylindricalbase t, snugly fittingthe interior of the thereto-appertaining insulating-tube at one end andholding up the said spring so that its cup 8 will be just below a holeor slot to in the upper side of the insulating-tube, through which holeor slot the corresponding bell k projects and reaches the said cup, anda small flange v at-the end of the base that is remote from the spring,to which flange either wire 19 is secured by a screw in. The clamps rare spring-clamps and firmly grasp the lamp-body, so as to hold theinsulating-tubes q and parts therein close enough to insure a perfectand permanent contact between the bells 7c and cups 8. The tubes q, itwill be noticed, completely insulate these clamps from the electriccircuit and allow them to be connected with any ordinary frame orbracket, though it be composed partly or wholly of inflammable material,the lamp resting in the said clamps being thereby rendered quite safe inits application and use to theextent that it is believed to fully complywith the strictest municipal fire regulations that are in forceanywhere.

It will be observed that I do not set forth the full and complete methodof manufacturing the lamp, and particularly the means by which thefilament is adjusted and anchored previously to the sealing of the tube,nor do I claim such portion of the process as is herein disclosed, forthe reason that the process of manufacturing lamps of this descriptionwill form the subject-matter of another application, and therefore Ihaveonly disclosed so .much of the process as is necessary to obtain afull and clear understanding of the invention presented, .and I desireit to be understood that I reserve all rights relative to such processin so far as it is herein set forth.

I claim 1. In an incandescentlamp, the combination with a receptacle, ofa filament received therein, anchors located within the receptacle, theinner ends of the anchors extending in alinement with and secured to theends of the filament, the outer ends of the anchors protrudingexteriorly of thereceptacle and means engaging the outer ends of theanchors and connected with a source of electrical energy, the terminalends of the anchors within the receptacle extending transversely to thefilament and the walls of the receptacle and means for supporting thereceptacle.

2. In an incandescent lamp, the combination with a tube, of a filamenttherein, anchors, the inner ends of which anchors are secured t0 thefilament, the terminal ends of the anchors within. the tube extendingapproximately transversely to the inner ends thereof and the filamentand protruding from the tube at points at a distance from thesealing-points of the tube. g

3. In an incandescent lamp, the combination with a tube, of a filamenttherein, and means for constantly and automatically sustaining thefilament in a straight line, the means com-' prising an anchor-conductorsecured to one end of the filament and protruding exteriorly of thetube, the terminal end of the anchorconductor within the tube extendingsubstantially transversely to the walls of the tube and to the filament.I

4;. In an incandescent lamp comprising a tube sealed at its oppositeends, the ends being uncovered, a filamentwithin the tube andanchor-conductors secured to the filament the anchors located within thetube, one of the anchors comprising an approximately angular member andthe other anchor comprising an angular member having a coil formedtherein, the inner ends of the anchors secured to the filament inalinement therewith, the outer ends of the anchors extendingapproximately transversely to the inner ends and protruding through thelongitudinal walls of the tube at points at a distance from the sealedends thereof.

5. In an electric lamp, the combination with a tube sealed at itsopposite ends, of a filament within the tube, anchors within the tubesecured to the filament, the terminal ends of the anchors protrudingfrom the tube at points at a distance from the sealed ends thereof, thewalls of the tube formed into a gland about each protruding end of theanchors, contactbells secured to the protruding ends of the anchors, thebells each secured to the gland as well, a suitable support for the tubeand means carried by the support and connected with a source ofelectrical energy, the means adapted to have removable engagement withthe contact-bells.

In testimony whereof I have signed my name to this specification in thepresence of two subscribing witnesses.

DENNIS JOSEPH OBRIEN. [1,. 8.]

Witnesses:

A. H. STE. MARIE, F. B. WORLEY.

IIO

